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From: Rahul Singh <rahul.singh@arm.com>
To: xen-devel@lists.xenproject.org
Cc: bertrand.marquis@arm.com, rahul.singh@arm.com,
	Andre.Przywara@arm.com,
	"Stefano Stabellini" <sstabellini@kernel.org>,
	"Julien Grall" <julien@xen.org>,
	"Volodymyr Babchuk" <Volodymyr_Babchuk@epam.com>,
	"Andrew Cooper" <andrew.cooper3@citrix.com>,
	"George Dunlap" <george.dunlap@citrix.com>,
	"Ian Jackson" <iwj@xenproject.org>,
	"Jan Beulich" <jbeulich@suse.com>, "Wei Liu" <wl@xen.org>,
	"Roger Pau Monné" <roger.pau@citrix.com>
Subject: [PATCH v5 02/11] xen/arm: Add PHYSDEVOP_pci_device_(*add/remove) support for ARM
Date: Wed,  6 Oct 2021 18:40:28 +0100	[thread overview]
Message-ID: <0dc4423b2e20c1eb40c961b211b18ed041f707b7.1633540842.git.rahul.singh@arm.com> (raw)
In-Reply-To: <cover.1633540842.git.rahul.singh@arm.com>

Hardware domain is in charge of doing the PCI enumeration and will
discover the PCI devices and then will communicate to XEN via hyper
call PHYSDEVOP_pci_device_add(..) to add the PCI devices in XEN.

Also implement PHYSDEVOP_pci_device_remove(..) to remove the PCI device.

As most of the code for PHYSDEVOP_pci_device_* is the same between x86
and ARM, move the code to a common file to avoid duplication.

There are other PHYSDEVOP_pci_device_* operations to add PCI devices.
Currently implemented PHYSDEVOP_pci_device_remove(..) and
PHYSDEVOP_pci_device_add(..) only as those are minimum required to
support PCI passthrough on ARM.

Signed-off-by: Rahul Singh <rahul.singh@arm.com>
---
Change in v5:
- Move the pci_physdev_op() stub to xen/arch/arm/physdev.c.
Change in v4:
- Move file commom/physdev.c to drivers/pci/physdev.c
- minor comments.
Change in v3: Fixed minor comment.
Change in v2:
- Add support for PHYSDEVOP_pci_device_remove()
- Move code to common code
---
---
 xen/arch/arm/physdev.c        |  6 ++-
 xen/arch/x86/physdev.c        | 52 +----------------------
 xen/arch/x86/x86_64/physdev.c |  2 +-
 xen/drivers/pci/Makefile      |  1 +
 xen/drivers/pci/physdev.c     | 80 +++++++++++++++++++++++++++++++++++
 xen/include/public/arch-arm.h |  4 +-
 xen/include/xen/hypercall.h   |  4 ++
 7 files changed, 96 insertions(+), 53 deletions(-)
 create mode 100644 xen/drivers/pci/physdev.c

diff --git a/xen/arch/arm/physdev.c b/xen/arch/arm/physdev.c
index e91355fe22..f9aa274dda 100644
--- a/xen/arch/arm/physdev.c
+++ b/xen/arch/arm/physdev.c
@@ -8,13 +8,17 @@
 #include <xen/lib.h>
 #include <xen/errno.h>
 #include <xen/sched.h>
-#include <asm/hypercall.h>
+#include <xen/hypercall.h>
 
 
 int do_physdev_op(int cmd, XEN_GUEST_HANDLE_PARAM(void) arg)
 {
+#ifdef CONFIG_HAS_PCI
+    return pci_physdev_op(cmd, arg);
+#else
     gdprintk(XENLOG_DEBUG, "PHYSDEVOP cmd=%d: not implemented\n", cmd);
     return -ENOSYS;
+#endif
 }
 
 /*
diff --git a/xen/arch/x86/physdev.c b/xen/arch/x86/physdev.c
index 23465bcd00..ea38be8b79 100644
--- a/xen/arch/x86/physdev.c
+++ b/xen/arch/x86/physdev.c
@@ -12,7 +12,7 @@
 #include <asm/io_apic.h>
 #include <asm/msi.h>
 #include <asm/hvm/irq.h>
-#include <asm/hypercall.h>
+#include <xen/hypercall.h>
 #include <public/xen.h>
 #include <public/physdev.h>
 #include <xsm/xsm.h>
@@ -480,54 +480,6 @@ ret_t do_physdev_op(int cmd, XEN_GUEST_HANDLE_PARAM(void) arg)
         break;
     }
 
-    case PHYSDEVOP_pci_device_add: {
-        struct physdev_pci_device_add add;
-        struct pci_dev_info pdev_info;
-        nodeid_t node;
-
-        ret = -EFAULT;
-        if ( copy_from_guest(&add, arg, 1) != 0 )
-            break;
-
-        pdev_info.is_extfn = !!(add.flags & XEN_PCI_DEV_EXTFN);
-        if ( add.flags & XEN_PCI_DEV_VIRTFN )
-        {
-            pdev_info.is_virtfn = 1;
-            pdev_info.physfn.bus = add.physfn.bus;
-            pdev_info.physfn.devfn = add.physfn.devfn;
-        }
-        else
-            pdev_info.is_virtfn = 0;
-
-        if ( add.flags & XEN_PCI_DEV_PXM )
-        {
-            uint32_t pxm;
-            size_t optarr_off = offsetof(struct physdev_pci_device_add, optarr) /
-                                sizeof(add.optarr[0]);
-
-            if ( copy_from_guest_offset(&pxm, arg, optarr_off, 1) )
-                break;
-
-            node = pxm_to_node(pxm);
-        }
-        else
-            node = NUMA_NO_NODE;
-
-        ret = pci_add_device(add.seg, add.bus, add.devfn, &pdev_info, node);
-        break;
-    }
-
-    case PHYSDEVOP_pci_device_remove: {
-        struct physdev_pci_device dev;
-
-        ret = -EFAULT;
-        if ( copy_from_guest(&dev, arg, 1) != 0 )
-            break;
-
-        ret = pci_remove_device(dev.seg, dev.bus, dev.devfn);
-        break;
-    }
-
     case PHYSDEVOP_prepare_msix:
     case PHYSDEVOP_release_msix: {
         struct physdev_pci_device dev;
@@ -663,7 +615,7 @@ ret_t do_physdev_op(int cmd, XEN_GUEST_HANDLE_PARAM(void) arg)
     }
 
     default:
-        ret = -ENOSYS;
+        ret = pci_physdev_op(cmd, arg);
         break;
     }
 
diff --git a/xen/arch/x86/x86_64/physdev.c b/xen/arch/x86/x86_64/physdev.c
index 0a50cbd4d8..e3cbd5ebcb 100644
--- a/xen/arch/x86/x86_64/physdev.c
+++ b/xen/arch/x86/x86_64/physdev.c
@@ -9,7 +9,7 @@ EMIT_FILE;
 #include <compat/xen.h>
 #include <compat/event_channel.h>
 #include <compat/physdev.h>
-#include <asm/hypercall.h>
+#include <xen/hypercall.h>
 
 #define do_physdev_op compat_physdev_op
 
diff --git a/xen/drivers/pci/Makefile b/xen/drivers/pci/Makefile
index a98035df4c..972c923db0 100644
--- a/xen/drivers/pci/Makefile
+++ b/xen/drivers/pci/Makefile
@@ -1 +1,2 @@
 obj-y += pci.o
+obj-y += physdev.o
diff --git a/xen/drivers/pci/physdev.c b/xen/drivers/pci/physdev.c
new file mode 100644
index 0000000000..4f3e1a96c0
--- /dev/null
+++ b/xen/drivers/pci/physdev.c
@@ -0,0 +1,80 @@
+
+#include <xen/guest_access.h>
+#include <xen/hypercall.h>
+#include <xen/init.h>
+
+#ifndef COMPAT
+typedef long ret_t;
+#endif
+
+ret_t pci_physdev_op(int cmd, XEN_GUEST_HANDLE_PARAM(void) arg)
+{
+    ret_t ret;
+
+    switch ( cmd )
+    {
+    case PHYSDEVOP_pci_device_add: {
+        struct physdev_pci_device_add add;
+        struct pci_dev_info pdev_info;
+        nodeid_t node = NUMA_NO_NODE;
+
+        ret = -EFAULT;
+        if ( copy_from_guest(&add, arg, 1) != 0 )
+            break;
+
+        pdev_info.is_extfn = (add.flags & XEN_PCI_DEV_EXTFN);
+        if ( add.flags & XEN_PCI_DEV_VIRTFN )
+        {
+            pdev_info.is_virtfn = true;
+            pdev_info.physfn.bus = add.physfn.bus;
+            pdev_info.physfn.devfn = add.physfn.devfn;
+        }
+        else
+            pdev_info.is_virtfn = false;
+
+#ifdef CONFIG_NUMA
+        if ( add.flags & XEN_PCI_DEV_PXM )
+        {
+            uint32_t pxm;
+            size_t optarr_off = offsetof(struct physdev_pci_device_add, optarr) /
+                                sizeof(add.optarr[0]);
+
+            if ( copy_from_guest_offset(&pxm, arg, optarr_off, 1) )
+                break;
+
+            node = pxm_to_node(pxm);
+        }
+#endif
+
+        ret = pci_add_device(add.seg, add.bus, add.devfn, &pdev_info, node);
+        break;
+    }
+
+    case PHYSDEVOP_pci_device_remove: {
+        struct physdev_pci_device dev;
+
+        ret = -EFAULT;
+        if ( copy_from_guest(&dev, arg, 1) != 0 )
+            break;
+
+        ret = pci_remove_device(dev.seg, dev.bus, dev.devfn);
+        break;
+    }
+
+    default:
+        ret = -ENOSYS;
+        break;
+    }
+
+    return ret;
+}
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
diff --git a/xen/include/public/arch-arm.h b/xen/include/public/arch-arm.h
index 6b5a5f818a..d46c61fca9 100644
--- a/xen/include/public/arch-arm.h
+++ b/xen/include/public/arch-arm.h
@@ -107,7 +107,9 @@
  *   All generic sub-operations
  *
  *  HYPERVISOR_physdev_op
- *   No sub-operations are currenty supported
+ *   Exactly these sub-operations are supported:
+ *   PHYSDEVOP_pci_device_add
+ *   PHYSDEVOP_pci_device_remove
  *
  *  HYPERVISOR_sysctl
  *   All generic sub-operations, with the exception of:
diff --git a/xen/include/xen/hypercall.h b/xen/include/xen/hypercall.h
index 3771487a30..07b10ec230 100644
--- a/xen/include/xen/hypercall.h
+++ b/xen/include/xen/hypercall.h
@@ -45,6 +45,10 @@ extern long
 do_platform_op(
     XEN_GUEST_HANDLE_PARAM(xen_platform_op_t) u_xenpf_op);
 
+extern long
+pci_physdev_op(
+    int cmd, XEN_GUEST_HANDLE_PARAM(void) arg);
+
 /*
  * To allow safe resume of do_memory_op() after preemption, we need to know
  * at what point in the page list to resume. For this purpose I steal the
-- 
2.25.1



  parent reply	other threads:[~2021-10-06 17:41 UTC|newest]

Thread overview: 190+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-10-06 17:40 [PATCH v5 00/11] PCI devices passthrough on Arm Rahul Singh
2021-10-06 17:40 ` [PATCH v5 01/11] xen/arm: xc_domain_ioport_permission(..) not supported on ARM Rahul Singh
2021-10-11 11:47   ` Roger Pau Monné
2021-10-11 12:11     ` Bertrand Marquis
2021-10-11 13:20       ` Roger Pau Monné
2021-10-11 13:40         ` Bertrand Marquis
2021-10-11 13:57           ` Roger Pau Monné
2021-10-11 14:16             ` Bertrand Marquis
2021-10-11 16:32               ` Roger Pau Monné
2021-10-11 17:11                 ` Bertrand Marquis
2021-10-12  8:29                   ` Jan Beulich
2021-10-12  8:41                     ` Bertrand Marquis
2021-10-12  9:32                       ` Jan Beulich
2021-10-12  9:38                         ` Oleksandr Andrushchenko
2021-10-12 10:01                           ` Jan Beulich
2021-10-12 10:06                             ` Oleksandr Andrushchenko
2021-10-12 10:20                               ` Jan Beulich
2021-10-12 10:41                                 ` Bertrand Marquis
2021-10-12 10:44                                   ` Jan Beulich
2021-10-12 14:53                                   ` Ian Jackson
2021-10-12 16:15                                     ` Bertrand Marquis
2021-10-12 16:29                                       ` Ian Jackson
2021-10-12 20:42                                         ` Stefano Stabellini
2021-10-13  8:07                                           ` Roger Pau Monné
2021-10-13 11:52                                             ` Ian Jackson
2021-10-13  8:02                                       ` Roger Pau Monné
2021-10-13 12:02                                         ` Ian Jackson
2021-10-12  9:40                         ` Bertrand Marquis
2021-10-12 10:03                           ` Jan Beulich
2021-10-11 14:16           ` Oleksandr Andrushchenko
2021-10-06 17:40 ` Rahul Singh [this message]
2021-10-07  0:05   ` [PATCH v5 02/11] xen/arm: Add PHYSDEVOP_pci_device_(*add/remove) support for ARM Stefano Stabellini
2021-10-07 12:58     ` Jan Beulich
2021-10-21  9:28   ` xen/arm: Missing appropriate locking for the IOMMU (WAS Re: [PATCH v5 02/11] xen/arm: Add PHYSDEVOP_pci_device_(*add/remove) support for ARM) Julien Grall
2021-10-21 13:15     ` Bertrand Marquis
2021-10-21 13:47       ` Julien Grall
2021-10-21 13:52         ` Bertrand Marquis
2021-10-06 17:40 ` [PATCH v5 03/11] xen/arm: Add cmdline boot option "pci-passthrough = <boolean>" Rahul Singh
2021-10-07  8:27   ` Jan Beulich
2021-10-07  8:32     ` Rahul Singh
2021-10-07 12:59   ` Jan Beulich
2021-10-06 17:40 ` [PATCH v5 04/11] xen/arm: PCI host bridge discovery within XEN on ARM Rahul Singh
2021-10-06 17:40 ` [PATCH v5 05/11] xen/arm: Add support for Xilinx ZynqMP PCI host controller Rahul Singh
2021-10-06 17:40 ` [PATCH v5 06/11] xen/arm: Implement pci access functions Rahul Singh
2021-10-06 17:40 ` [PATCH v5 07/11] xen/domctl: Introduce XEN_DOMCTL_CDF_vpci flag Rahul Singh
2021-10-07 13:08   ` Jan Beulich
2021-10-08 18:06   ` Andrew Cooper
2021-10-08 21:12     ` Julien Grall
2021-10-08 21:46       ` Stefano Stabellini
2021-10-11  9:24         ` Julien Grall
2021-10-11 11:29         ` Michal Orzel
2021-10-11 11:35           ` Jan Beulich
2021-10-11 13:17             ` Roger Pau Monné
2021-10-11  9:48     ` Ian Jackson
2021-10-11  9:27   ` Roger Pau Monné
2021-10-11 12:06     ` Michal Orzel
2021-10-12 10:38     ` Michal Orzel
2021-10-13  8:30       ` Roger Pau Monné
2021-10-13  9:36         ` Bertrand Marquis
2021-10-13 10:56           ` Roger Pau Monné
2021-10-13 12:11             ` Bertrand Marquis
2021-10-13 12:57               ` Jan Beulich
2021-10-13 20:41                 ` Stefano Stabellini
2021-10-14  6:23                   ` Jan Beulich
2021-10-14  7:53                     ` Bertrand Marquis
2021-10-13 14:28               ` Roger Pau Monné
2021-10-13 20:53             ` Stefano Stabellini
2021-10-13 23:21               ` Stefano Stabellini
2021-10-12 21:48     ` Stefano Stabellini
2021-10-13  6:18       ` Jan Beulich
2021-10-13  7:11         ` Michal Orzel
2021-10-06 17:40 ` [PATCH v5 08/11] xen/arm: Enable the existing x86 virtual PCI support for ARM Rahul Singh
2021-10-07 13:43   ` Jan Beulich
2021-10-11 12:41     ` Bertrand Marquis
2021-10-11 13:09       ` Jan Beulich
2021-10-11 13:34         ` Bertrand Marquis
2021-10-11 14:10           ` Jan Beulich
2021-10-11 14:52             ` Bertrand Marquis
2021-10-11 18:18             ` Stefano Stabellini
2021-10-12  8:04               ` Jan Beulich
2021-10-12 21:37                 ` Stefano Stabellini
2021-10-13  6:10                   ` Jan Beulich
2021-10-13 10:02                     ` Bertrand Marquis
2021-10-13 12:21                       ` Jan Beulich
2021-10-12 15:04       ` Julien Grall
2021-10-12 16:12         ` Bertrand Marquis
2021-10-12 16:20           ` Julien Grall
2021-10-12 17:50             ` Bertrand Marquis
2021-10-11 10:51   ` Roger Pau Monné
2021-10-11 16:12     ` Bertrand Marquis
2021-10-11 16:20       ` Oleksandr Andrushchenko
2021-10-11 16:43         ` Roger Pau Monné
2021-10-11 17:15           ` Bertrand Marquis
2021-10-11 18:30             ` Oleksandr Andrushchenko
2021-10-11 19:27               ` Stefano Stabellini
2021-10-12  5:34                 ` Oleksandr Andrushchenko
2021-10-12  7:44                 ` Bertrand Marquis
2021-10-12 14:32   ` Julien Grall
2021-10-12 14:34     ` Bertrand Marquis
2021-10-13  8:45   ` Roger Pau Monné
2021-10-13  9:48     ` Bertrand Marquis
2021-10-13 10:33       ` Roger Pau Monné
2021-10-13 13:00     ` Jan Beulich
2021-10-13 14:51       ` Oleksandr Andrushchenko
2021-10-13 15:15         ` Jan Beulich
2021-10-13 19:27           ` Stefano Stabellini
2021-10-14  6:33             ` Jan Beulich
2021-10-14  7:53               ` Bertrand Marquis
2021-10-14  9:03               ` Bertrand Marquis
2021-10-14  9:24                 ` Jan Beulich
2021-10-06 17:40 ` [PATCH v5 09/11] xen/arm: Transitional change to build HAS_VPCI on ARM Rahul Singh
2021-10-11 11:43   ` Roger Pau Monné
2021-10-11 12:15     ` Bertrand Marquis
2021-10-12  1:32       ` Stefano Stabellini
2021-10-06 17:40 ` [PATCH v5 10/11] arm/libxl: Emulated PCI device tree node in libxl Rahul Singh
2021-10-06 18:01   ` Julien Grall
2021-10-07  0:26     ` Stefano Stabellini
2021-10-07 15:31       ` Rahul Singh
2021-10-07 10:53     ` Ian Jackson
2021-10-07 15:29       ` Rahul Singh
2021-10-07 16:11         ` Ian Jackson
2021-10-11 13:46           ` Roger Pau Monné
2021-10-14 17:16           ` Bertrand Marquis
2021-10-14 14:49             ` [PATCH v6 0/3] PCI devices passthrough on Arm Bertrand Marquis
2021-10-14 14:49               ` [PATCH v6 1/3] xen/vpci: Move ecam access functions to common code Bertrand Marquis
2021-10-14 16:06                 ` Jan Beulich
2021-10-14 17:09                   ` Bertrand Marquis
2021-10-15  6:29                     ` Jan Beulich
2021-10-15  7:37                       ` Bertrand Marquis
2021-10-15  8:13                         ` Jan Beulich
2021-10-15  8:20                           ` Bertrand Marquis
2021-10-15  8:24                             ` Jan Beulich
2021-10-15  9:49                           ` Roger Pau Monné
2021-10-14 23:47                 ` Stefano Stabellini
2021-10-15  7:44                 ` Roger Pau Monné
2021-10-15  7:53                   ` Bertrand Marquis
2021-10-15  9:53                     ` Roger Pau Monné
2021-10-15 10:12                       ` Bertrand Marquis
2021-10-15 10:14                       ` Jan Beulich
2021-10-14 14:49               ` [PATCH v6 2/3] xen/arm: Enable the existing x86 virtual PCI support for ARM Bertrand Marquis
2021-10-14 23:49                 ` Stefano Stabellini
2021-10-15  6:40                   ` Jan Beulich
2021-10-15  9:59                     ` Ian Jackson
2021-10-15 10:10                   ` Bertrand Marquis
2021-10-15  8:00                 ` Jan Beulich
2021-10-15 10:09                   ` Bertrand Marquis
2021-10-15 10:14                     ` Ian Jackson
2021-10-15 10:18                       ` Jan Beulich
2021-10-15 11:35                         ` Roger Pau Monné
2021-10-15 12:13                           ` Bertrand Marquis
2021-10-15 12:18                             ` Jan Beulich
2021-10-15 12:28                               ` Bertrand Marquis
2021-10-15 13:00                                 ` Jan Beulich
2021-10-15 13:10                                   ` Bertrand Marquis
2021-10-15 10:38                     ` Jan Beulich
2021-10-15  8:32                 ` Roger Pau Monné
2021-10-15  8:42                   ` Michal Orzel
2021-10-15  9:52                   ` Bertrand Marquis
2021-10-15 10:13                     ` Luca Fancellu
2021-10-15 10:17                       ` Bertrand Marquis
2021-10-15 10:19                     ` Roger Pau Monné
2021-10-15 10:31                       ` Bertrand Marquis
2021-10-15 10:24                     ` Jan Beulich
2021-10-15 10:33                       ` Bertrand Marquis
2021-10-15 10:41                         ` Jan Beulich
2021-10-15 10:48                           ` Bertrand Marquis
2021-10-15 10:51                             ` Jan Beulich
2021-10-15 11:08                               ` Bertrand Marquis
2021-10-15 13:47                             ` Roger Pau Monné
2021-10-15 14:00                               ` Luca Fancellu
2021-10-15 14:32                                 ` Roger Pau Monné
2021-10-14 14:49               ` [PATCH v6 3/3] arm/libxl: Emulated PCI device tree node in libxl Bertrand Marquis
2021-10-14 17:54                 ` [PATCH v6 3/3] arm/libxl: Emulated PCI device tree node in libxl [and 1 more messages] Ian Jackson
2021-10-14 23:50                   ` Stefano Stabellini
2021-10-15  7:28                   ` Julien Grall
2021-10-15  7:41                     ` Michal Orzel
2021-10-15  9:01                       ` Julien Grall
2021-10-15 10:02                     ` Ian Jackson
2021-10-15 10:58                       ` Michal Orzel
2021-10-15 11:04                         ` Michal Orzel
2021-10-15 11:46                         ` Ian Jackson
2021-10-15 11:53                           ` Michal Orzel
2021-10-15 12:10                             ` Julien Grall
2021-10-15 12:14                               ` Ian Jackson
2021-10-15 12:13                             ` Ian Jackson
2021-10-12 15:03   ` [PATCH v5 10/11] arm/libxl: Emulated PCI device tree node in libxl Ian Jackson
2021-10-06 17:40 ` [PATCH v5 11/11] xen/arm: Add linux,pci-domain property for hwdom if not available Rahul Singh
2021-10-13 20:54   ` Stefano Stabellini
2021-10-07 19:54 ` [PATCH v5 00/11] PCI devices passthrough on Arm Stefano Stabellini
2021-10-07 21:29   ` Rahul Singh

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